Backing Up the Library
An option in Lightroom’s General preferences allows you to create an automatic scheduled backup of the master Lightroom library file at a frequency of your choosing. I strongly advise selecting one of these options, in order to gain an extra level of built-in backup security that may well prevent you from losing valuable library data information.
When you select a scheduled library backup option, the dialog box in Figure 1 appears each time a scheduled backup is due. You can specify a location where the backup library file should be stored, as well as run a test to see whether the database is corrupted. If the file is corrupted, Lightroom offers the opportunity to replace the current (corrupted) database with the previously backed-up database copy file.
Figure 1 Lightroom asks you to confirm that you want to back up the library.